Alexa Internet, Inc. was a web traffic analysis company based in San Francisco, California.

Alexa provided web traffic data, global rankings, and other information on over 30 million websites.

[citation needed] Alexa Internet was founded in April 1996 by Brewster Kahle and Bruce Gilliat.

[11][12] This database served as the basis for the creation of the Internet Archive, accessible through the Wayback Machine.

In 1999, as the company moved away from its original vision of providing an "intelligent" search engine, Alexa was acquired by Amazon.com for approximately US$250 million in Amazon stock.

[15] In December 2005, Alexa opened its extensive search index and Web-crawling facilities to third-party programs through a comprehensive set of Web services and APIs.

In April 2007, the company filed a lawsuit, Alexa v. Hornbaker, to stop trademark infringement by the Statsaholic service.

[21] In the following weeks, Alexa added more features, including visitor demographics, clickstream, and web search traffic statistics.

[27] The traffic rank used to be determined from data recollected from users that had the Alexa toolbar installed on their browser.

The Alexa browser extension displayed the Alexa Traffic Rank for websites, showed related websites, provided search analytics, and quickly allowed users to view the Internet Archive through the Wayback Machine.

In early 2005, Alexa stated that there had been 10 million downloads of the toolbar, though the company did not provide statistics about active usage.

This caused some controversies over how representative Alexa's user base was of typical Internet behavior,[33] especially for less-visited sites.